The Demon King Doesn't Need to be Defeated

“I am a hero, from another world.”“The goddess summoned me to this world to defeat the Demon King who is harming the world, so that the world can restore peace.”“I understand that this is a great responsibility. Since I've been summoned and become a hero, then, even if the opponent is an incredibly powerful Demon King, I must put in all my effort to defeat him (her).”“Don't ask me why, just ask, and the books all say so.”“However... isn't this development a little off the script !!!?”This is the beginning of a cross-world deception, and it's also the story where the hero, carrying the mission of defeating the Demon King, finally discovers in amazement that he was set up.